Answer:
1. (10, -⁸/₃)
2. (2, ⁸/₃)
3. (12, -4)
Explanation:
I will do the first 3 as examples.
1. Y is ⅔ of the distance from X to Z.
Y − X = ⅔ (Z − X)
The x-coordinate of Y is:
x − -6 = ⅔ (18 − -6)
x + 6 = ⅔ (24)
x + 6 = 16
x = 10
The y-coordinate of Y is:
y − 8 = ⅔ (-8 − 8)
y − 8 = ⅔ (-16)
y − 8 = -³²/₃
y = -⁸/₃
Y is at (10, -⁸/₃).
2. The ratio of XY to YZ is 1:2.
(Y − X) / (Z − Y) = 1 / 2
Cross multiply.
2 (Y − X) = Z − Y
The x-coordinate of Y is:
2 (x − -6) = 18 − x
2x + 12 = 18 − x
3x = 6
x = 2
The y-coordinate of Y is:
2 (y − 8) = -8 − y
2y − 16 = -8 − y
3y = 8
y = ⁸/₃
Y is at (2, ⁸/₃).
3. Y is ¼ of the distance from Z to X.
Y − Z = ¼ (X − Z)
The x-coordinate of Y is:
x − 18 = ¼ (-6 − 18)
x − 18 = ¼ (-24)
x − 18 = -6
x = 12
The y-coordinate of Y is:
y − -8 = ¼ (8 − -8)
y + 8 = ¼ (16)
y + 8 = 4
y = -4
Y is at (12, -4).